1. Field of the Invention
The present invention relates to angle adjusting structures for high-hat cymbals which prevent angles of the high-hat cymbals from being involuntarily varied during performance.
The present application claims priority on Japanese Patent Application No. 2008-320553, the content of which is incorporated herein by reference.
2. Description of the Related Art
Conventionally, high-hat stands have been widely used to support high-hat cymbals and disclosed in various documents.                Patent Document 1: Japanese Utility Model No. 2559420        Patent Document 2: U.S. Pat. No. 7,078,606        
Patent Document 1 discloses a cymbal receiving structure for high-hat cymbals which includes a receiving plate for receiving the lower portion of the high-hat cymbals, a bolt disposed beneath the receiving plate, and a nut engaged with the bolt. The cymbal receiving structure adjusts a tilting angle of the high-hat cymbals in such a way that the bolt is revolved to move up/down so as to vary the tilting of the receiving plate above the bolt.
During performance, vibration and/or impact may easily cause the bolt to involuntarily revolve, thus involuntary varying the tilting angle of the high-hat cymbals. To avoid such an event, the cymbal receiving structure incorporates a lock nut engaged with the bolt, wherein after completion in adjusting the angle by revolving the bolt, the lock nut is operated to tighten the bolt and to thereby prevent the bolt from being involuntarily revolved.
Patent Document 2 discloses another structure for limiting the revolution of the bolt and the nut, wherein the nut is revolved to move the bolt up/down so as to adjust the tilting angle of the high-hat cymbals. This structure incorporates a spring that axially presses the bolt so as to increase the friction between the bolt and the nut, thus limiting the revolution of the nut.
The structure of Patent Document 1 needs the tightening of the lock nut in addition to the revolution of the bolt to limit the further revolution of the bolt. Every time the tilting angle of the high-hat cymbals needs adjusting, the structure needs to release the tightening of the lock nut and then to tighten the lock nut again. That is, the structure requires a troublesome and time-consuming operation to adjust the angle of the high-hat cymbals.
The structure of Patent Document 2 is disadvantageous in that increasing the resilience of the spring increases the power for revolting the nut and decreases the workability in adjusting the angle of the high-hat cymbals. Since the structure uses the friction of thread groves between the bolt and the nut in limiting the involuntary revolution of the bolt and the nut, repeated vibration and/or impact in performance briefly varies the friction and therefore causes difficulty in limiting the revolution of the bolt steadily. Decreasing the resilience of the spring may improve the workability but may cause further difficulty in limiting the revolution of the bolt during performance.